Useless

You get a card that is class specific, so assassins are only archers. and basically you transform into the specialist. your skills as the previous class are not there. so u lvl up as your specialist and u gain new skills only to your specialist. so your leveling up your card. players get 10k SP, and you lose 3 SP every time you fight. resting does not lose you SP. you can transform back to your other class and become another specialist but you still have the SP remaining for that day.
Sp recharges every 24 hours. so you can transform back and forth until u have 0 SP.

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